EP1704376B1 - Bulk material grate cooler comprising a regulating device for the cooling air flow - Google Patents

Description

The invention relates to a bulk material cooler, comprising a device for controlling the flow cross-section in the Kühlluftzuströmungen the Schüttgutrostkühlers for cooling a hot bulk material such. As cement clinker, with an integrated into the Kühlluftzströmströmung below the cooling grate controller housing in which an actuator moves such that an increase in the flow velocity in the region of the actuator and associated with a beginning increase in the cooling air flow causes reduction of the free flow cross-section and vice versa.

In a cement clinker production line, the burned in a rotary kiln of calcined cement raw meal hot cement clinker from the Ofenaustragsende on a cooler, usually on the cooling rack of a grate cooler, distributed on this and moved by suitable funding in the longitudinal direction to Kühleraustragsende, the cooling grid and the hot Bulk material layer are traversed essentially from bottom to top of cooling air flows. The known types of grate coolers will be briefly explained below.

In a sliding grate cooler in the conveying direction stationary grate plate rows alternate with reciprocating grate plate rows, all grate plates are provided with cooling air openings and they are traversed essentially from bottom to top of cooling air, and by the common oscillating movement of all movable grate plate rows the hot material to be cooled is transported in batches and thereby cooled. As an alternative to such a sliding grate cooler z. B. from the EP-B-1 021 692 a type of grate cooler is known in which the cooling air flowed through cooling grate is not moved, but fixed, above the fixed grate surface a plurality of rows of adjacent reciprocating bar-shaped pushers are arranged, which are moved between a Vorhubposition in Kühlguttransportrichtung and a Rückhubposition, so that the reciprocating motion of these pushers in the cooled good bed material also successively moved from the radiator start to the radiator end and thereby cooled.

With such grate coolers, unequal distributions in the hot bulk material bed with respect to bulk material bed height, clinker grain size, temperature profile etc. can not always be avoided, which results in uneven cooling. Because in cooling grate areas with larger bulk material bed height, the flow resistance for the cooling air increases, it decreases the flow velocity and less cooling air is passed through the bulk bed, and vice versa falls in cooling grate areas with low bulk bed height of the flow resistance for the cooling air, their flow velocity and the risk of air leakage increase , And it is a too high amount of cooling air passed straight through such bulk bed areas, which would require the least amount of cooling air.

It is therefore known in a grate cooler for cooling of hot bulk material such as cement clinker ( EP-B-0 848 646 ), in the Kühlluftzuströmungen below the cooling grate, the respective amount of cooling air automatically in each case to be regulated so that at the beginning of increase in the cooling air flow, caused by decreasing Kühlgutbetthöhe and decreasing flow resistance, the clear cross-sectional area of the respective Kühlluftzuströmungsleitungen is reduced and vice versa, in order to compensate for a changing pressure drop across the Kühlgutbett so that the respective amount of cooling air is no longer dependent on the respective pressure loss or flow resistance of the cooling air in the respective Kühlgutbettzone. In this case, the known mechanical cooling air flow rate controller operates with a weight-loaded pendulum flap with horizontal pivot axis, the pendulum flap throttles more or less automatically depending on the prevailing pressure conditions and flow conditions the respective Kühlluftzströmömung. If you were the known cooling air control device, which works automatically with a purely by gravity swivel lever weight with Anströmkörper, below the cooling grate in the Kühlluftzuströmungen of cooling grate zones, which are not fixed, but which are reciprocated like a grate cooler for the purpose of bulk transport together with control devices, so the automatic control of the control device would be disturbed by the reciprocating shaking and the result of the regulation would be falsified.

Also from the WO 02/06748 in a bulk material cooler a cooling air control device is known in which in the cooling air supply line below the grate a round provided with through holes fixed segment disc and above a rotatably supported on an axis wing disc are arranged, which latter rotates depending on the flow velocity of the cooling air and thereby the clear Flow cross-section of the segment disc in the manner changed automatically in such a way that with an increase in the flow velocity, the wing disc is rotated against a spring force and the flow cross-section is reduced, and vice versa. Even with this self-acting working cooling air control device, the risk is not excluded that the function of the control device is disturbed by the pulsating pendulum motion of the reciprocating cooling grate zones.

Finally, in US Patent US 3,540,484 A discloses a cylindrical constant volume controller for use in air distributors of air conditioning systems. This constant air flow regulator has air passage openings in the cylindrical shell.

The invention has for its object to provide a Schüttgutrostkühler having an automatically operating cooling air control device according to the preamble of claim 1 in such a way that the cooling air control device easily built and easily both for non-moving and especially for moving cooling grate areas or moving cooling grate systems of a grate cooler for cooling in particular hot cement clinker can be used.

This object is achieved according to the invention with a bulk material cooler, comprising a control device having the features of claim 1. Advantageous developments of the invention are specified in the subclaims.

The control devices arranged in the cooling air inflows below the cooling grate of a bulk material cooler each have a controller housing through which the cooling air flows in as well as an actuating element movable therein. It is characteristic of a bulk material cooler according to the invention that in the hollow body-like regulator housing through which cooling air flows essentially from below upwards, an inner body translationally movable in translation from the cooling air flow is displaceably guided and automatically movable by the cooling air flow. The transverse to the main flow direction of the cooling air flow inner body may, for. B. guided on a central axis within the regulator housing be. A displacement of the inner body causes the change in the remaining free flow cross-section for the cooling air flow in such a way that an increase in the flow velocity of the cooling air in the region of the inner body and associated an incipient increase in the cooling air flow rate, a reduction of

Flow cross-section of the controller housing causes, and vice versa. The translational displacement of the inner body in the controller housing is done against the action of a restoring force. For this purpose can attack at the center of the inner body with advantage at least one return spring, which can be held by the axis of the controller housing and the flow area of the controller housing keeps open in the absence of the cooling air flow.

In the operation of the automatically operating cooling air control device of the bulk material cooler according to the invention, gravity and moments of inertia, which could impair the function of the automatic control, are irrelevant. The cooling air control device according to the invention is therefore particularly suitable for use in bulk material coolers with moving cooling grate areas or moving cooling grate systems, d. H. So for the above-mentioned grate cooler as well as for cooling grate systems that work on the so-called walking floor conveyor principle, which will be explained in more detail below.

With particular advantage, the control characteristic of the control device can be adjusted and changed by changing the biasing force of the at least one return spring, namely z. B. such that the return spring is arranged around the regulator housing axis around helical spring whose end facing away from the actuator disc end is supported on an actuator which is screwed adjustably on the threaded end of the axle for the purpose of setting / changing the spring biasing force , In this way, the control characteristic as well as the desired value of the response of the control device according to the invention can be easily adjusted and changed.

The control characteristic can increase the cooling air requirement with increasing Kühlgutbetthöhe or rising Kühlgutbett-flow resistance for the cooling air. It can be used to control a substantially constant volume flow of the cooling air regardless of changes in the cooling air flow resistance.

The acting inside the regulator housing as an actuator inner body may be the shape z. As a disc, a pot-like pipe section, etc. have. The actuator acting on the return spring may be instead of a helical spring also another spring element having a certain biasing force. It would also be possible to completely dispense with a return spring and adjust the weight of the inner body so that only the weight force acts as a restoring force for the inner body.

Instead of a z. B. central axis of the inner body can be guided translationally movable at its peripheral edge in the regulator housing, so that in this case can account for a guide axis.

The automatic regulation of the volume flow of the cooling air flowing through the cooling grate, according to an embodiment of the invention by a control device with z. B. cylindrical regulator housing having a plurality of over the length or height and circumferentially distributed openings, wherein the cooling air flows through these openings into the interior of the regulator housing and at the top, which flanged to the underside of the cooling grate is, flows out into the cooling grate. Should the pressure loss of the outflowing cooling air fall off in the bulk material bed, more cooling air would want to flow through the grate cooler. However, if the flow velocity of the cooling air increases, then the axially guided inner body, which in turn may have cooling air flow openings, moves by a certain amount from below to the top, wherein the number of remaining in the controller housing above the inner body cool air flow through openings and thus the amount of incoming in this way in the controller housing cooling air is reduced. At the same time, the amount of cooling air flowing through the openings of the disc-shaped part of the inner body may increase, so that a total of substantially constant automatic control of the volume flow amount of the cooling air is achieved.

The controller housing, instead of the plurality of distributed over the height and the circumference cooling air passage openings only at least a single z. B. spiral from bottom to top opening, so that in this case with displacement of the inner body up the cooling air volume flow is reduced, and vice versa.

The automatic regulation of the volume flow of the cooling air through the grate cooler can according to a further embodiment of the invention with a z. B. round control housing can be achieved, which has a conical cross-sectional constriction extending in the flow direction, wherein in the region of the housing cone of the flow of cooling air flowed from below inner body is arranged so that caused by the cooling air flow axial displacement of the inner body, the change of the free flow cross-section between the Inner body edge and the housing cone and connected thereto causes an automatic regulation of the cooling air volume flow.

The invention and its further features and advantages will be explained in more detail with reference to the embodiments schematically illustrated in the figures.

Fig. 1:

in perspektivischer Ansicht ein erstes Ausführungsbeispiel der Kühlluft-Regelungsvorrichtung des erfindungsgemäßen Schüttgutrostkühlers bei der zwecks Einblick in das Innere ein vorderes Teilstück des Reglergehäuses herausgeschnitten ist,

Fig. 2:

ebenfalls in perspektivischer Ansicht ein zweites Ausführungsbeispiel der Kühlluft-Regelungsvorrichtung des erfindungsgemäßen Schüttgutrostkühlers, bei der wiederum zwecks Einblick in das Innere ein vorderes Teilstück des Reglergehäuses herausgeschnitten ist, und

Fig. 3:

ebenfalls in perspektivischer Ansicht ein Kühlrost-Modul eines Schüttgutkühlers mit an der Kühlrostunterseite angebauten Kühlluft-Regelungsvorrichtungen der vorgenannten Figuren, wobei aus einer Vielzahl solcher hintereinander und nebeneinander angeordneten Module der Kühlrost eines Schüttgutkühlers zusammengesetzt ist.

It shows:

Fig. 1:

a perspective view of a first embodiment of the cooling air control device of the bulk material cooler according to the invention in which a front portion of the regulator housing is cut out for the purpose of insight into the interior,

Fig. 2:

likewise a perspective view of a second embodiment of the cooling air control device of the bulk material cooler according to the invention, in which in turn for the purpose of insight into the interior, a front portion of the regulator housing is cut out, and

3:

likewise a perspective view of a cooling grid module of a bulk material cooler with cooling air control devices of the abovementioned figures attached to the bottom of the cooling grid, the cooling grid of a bulk material cooler being composed of a large number of such modules arranged one behind the other and next to one another.

The of the cooling air 10 of a grate cooler for cooling hot bulk such. B. cement clinker flowed through automatically operating control device of Fig. 1 , wherein a plurality of such control devices to the underside of in Fig. 3 Sectionally illustrated cooling grate is mounted, has a regulator housing 11 and an inner body 12 disposed therein. Housing 11 and inner body 12 are formed round; but they can also have a polygonal configuration. The disc-shaped inner body 12 is z. B. on a central axis 13 which is held at least at the top of struts 14 in the housing 11, in the main flow direction of the cooling air 10 automatically translatorisch guided guided, wherein a change in the pressure loss in the cooling air flow above the inner body or a change in the pressure difference between the underside and top of the inner body 12 causes an axial displacement of the inner body 12.

The controller housing 11 of Fig. 1 has z. B. a plurality of distributed over the length or height and around the circumference of the housing openings 15, wherein cooling air 10 flows through these openings 15 into the interior of the housing 11 and at the top 16, which flanged to the underside of the cooling grate is discharged through corresponding outlet openings on the top 16 in the cooling grid. At incipient drop in the pressure loss of the cooling air z. B. on the occasion of incipient air breakthrough in a grate cooler area with low Schüttgutbetthöhe the inner body 12 is automatically pushed by the cooling air flow up, and the number of cooling air flow openings 15 in the housing 11 is reduced, so that the amount of cooling air can be throttled automatically or kept substantially constant , The center of the inner body 12 has a bushing 17, with which the inner body is guided along the axis 13 of the regulator housing. At the center of the inner body 12 engages in the region of its sleeve 17 at least one return spring 18, which is arranged around the axis 13 around as a helical spring and held by the axle.

The inner body 12 may also advantageously have recesses such as holes 19, if only so that a minimum cooling air flow is maintained even if the inner body 12 should reach its highest altitude with the strongest throttle effect of the cooling air flow. In this way it is ensured that the cooling grid, even if the bulk material bed height should be reduced to zero, always remains cooled. The biasing force of the at least one return spring 18 is adjustable and changeable in such a way that the spring body remote from the inner body 12 at a for example, threaded actuator 20 is supported by which the spring biasing force is adjustable. In this way, the control characteristic of the control device according to the invention can be adjusted and changed.

If the inner body 12 also rotatably supported on its sleeve 17 on the regulator housing axis 13 and the inner body 12 is formed as an impeller, which is driven by the cooling air flow 10, the inner body 12 can still rotate in addition to its axial displacement, whereby the Response of the actuator can still be increased.

According to the further embodiment of the Fig. 2 the regulator housing 11 has three successive in the cooling air flow direction and merging into each other areas, namely a cross-sectionally cylindrical inflow region 21 and an adjoining frusto-conical in the flow direction tapered conical region 22, at the conically reduced cross section, a cylindrical outflow region 23 connects. The inner body 12 is in turn guided on a central axis 13, which is held in this case at the top and bottom of struts 14 in the housing 11, and it is in the flow direction of the cooling air 10 again automatically movable, wherein an axial displacement of the inner body 12 is a change of free flow cross-section between the inner body edge and the housing cone 22 causes in such a way that an increase in the flow velocity in the region of the inner body 12 z. B. on the occasion of incipient air breakthrough in a grate cooler area with low bulk bed height automatically causes a reduction of the free flow area and thus throttling the cooling air flow rate, and vice versa. Also, the control device of Fig. 2 can do that be configured that it allows a constant control of the volume flow of the cooling air 10 substantially.

The center of the inner body 12 faces Fig. 2 in turn, a bushing 17, with which the inner body is guided along the axis 13 of the regulator housing. At the center of the inner body 12 engages in the region of its bushing 17 at least one return spring 18, which is arranged around the axis 13 as a helical spring and held by the axis, and the gap between the inner body 12 and regulator housing cone 22 keeps open in the absence of the cooling air flow 10 ,

Also in the embodiment of Fig. 2 is the biasing force of the at least one return spring 18 adjustable and changeable in such a way that the remote from the inner body 12 spring end z. B. is supported on an adjusting nut 24 which is screwed adjustably on the threaded end of the axle 13 for the purpose of setting / changing the spring biasing force. Instead of or in addition to the compression spring 18 may also be a tension spring 18 a may be present, which cooperates with the other end of the axis 13. By changing the spring biasing force, the control characteristic of the control device according to the invention is also adjusted here and possibly changed depending on the situation of the cooler operation.

Analogous to the embodiment of Fig. 1 can also in the control device of Fig. 2 the inner body 12 may still be rotatably mounted, and the inner body 12 may also be provided with cooling air passage holes.

Out Fig. 3 It can be seen that a plurality of the cooling air control devices of Fig. 1 and / or alternatively Fig. 2 each with their upper outlet openings 25 for the cooling air flow 10th can be flanged to the cooling air inlet openings on the underside of a particular moving cooling grate to the cooling air supply. Explains on the cooling grid module the Fig. 3 each module according to the embodiment of three extending in the longitudinal direction of the radiator juxtaposed elongated approximately trough-shaped bottom elements 27, 28, 29 composed independently of each other between a Vorhubposition 30 in Kühlguttransportrichtung and a Rückhubposition 31 are movable so that the mounted on the floor elements there not shown hot chilled gradually z. B. is promoted by the cooler after the walking floor conveyor principle. The drive of the individual floor elements 27, 28, 29 of the cooling grate modules takes place from below the cooling grate on push frames, which are supported on rollers and which attack working cylinder, namely controlled so that the floor elements together forward, but not together, but separated in time be moved back from each other.

The bottom elements 27, 28, 29 of all modules are formed as a hollow body, namely they have in cross section a the Kühlgut-carrying and for the cooling air 10 substantially from bottom to top permeable top 32 and a spaced therefrom the Kühlgut-Rostdurchfall preventing bottom 33th on. In this case, the lower sides 33 of all floor elements on several distributed over the length of the cooling air inlet openings on which from below the in Fig. 1 respectively. Fig. 2 are shown flanged, of which in Fig. 3 the three controller housing 11 of the three independently movable cooling grid floor elements 27, 28, 29 can be seen. The cooling grid top sides 32 carrying the hot items to be cooled, such as cement clinker, can in principle be provided with any passages permeable to the cooling air 10. With particular advantage, the cooling grid tops 32 each consist of spaced apart mirror image opposite, but offset from one another saddle roof-shaped V-profiles, whose V-legs interlock with each other, which latter forms a labyrinth for the refrigerated goods and for the cooling air 10. This ensures that the bulk material cooler is protected against rust rust.

In Fig. 3 can still be seen that on the permeable to the cooling air 10 upper surface 32 of all bottom elements 27 to 29 transverse to Kühlguttransportrichtung webs 34a to 34c for holding the lowermost bulk material layer and to avoid relative movement of this lowermost layer and the respective grate floor element can be arranged, which contributes to the wear protection of these rust floor elements.

Claims (9)

1. Bulk material grate cooler, having a regulating device for regulating the flow cross section in the cooling air inflows of the bulk material grate cooler for cooling hot bulk material, with a regulator housing (11) which is integrated into the cooling air inflow (10) below the cooling grate of the bulk material grate cooler, a control element (12) being moved in such a way in the regulator housing (11) that an increase in the flow rate of the cooling air (10) in the region of the control element (12) and, associated therewith, an incipient increase in the cooling air flow quantity bring about a reduction in the free flow cross section, and vice versa, characterized in that
   the control element (12), as an inner body (12) which can be moved translatorily by the cooling air flow (10), is guided displaceably counter to the action of a restoring force in the regulator housing (11) through which cooling air (10) supplied flows,
   with increasing height inside the regulator housing (11) of the inner body (12) against which the cooling air (10) flows, the free flow cross section of the regulator housing remaining for the cooling air (10) being reduced, and vice versa.
2. Bulk material grate cooler according to Claim 1, characterized in that the regulator housing (11) has at least one opening (15) distributed over the length or height and around the periphery, the cooling air (10) flowing into the interior of the regulator housing (11) through this at least one opening and flowing out into the cooling grate on the upper side (16) of the housing, which is flanged onto the lower side of the cooling grate, and axial displacement of the inner body (12) varying the flow cross section of the at least one opening (15) flowed through by cooling air.
3. Bulk material grate cooler according to Claim 1, characterized in that the regulator housing (11) has a conical cross-sectional narrowing extending in the flow direction, and in that the inner body (12) is arranged in the region of the housing cone (22), axial displacement of the inner body (12) causing the free flow cross section between the inner body edge and the housing cone (22) to change.
4. Bulk material grate cooler according to one of Claims 1 to 3, characterized in that the cross section of the regulator housing (11) and the periphery of the inner body (12) are round or polygonal.
5. Bulk material grate cooler according to Claim 1, characterized in that the regulating characteristic of the regulating device is settable and variable by means of changing the preloading force of at least one restoring spring (18).
6. Bulk material grate cooler according to Claim 5, characterized in that the restoring spring (18) is a helical spring which is arranged around the regulator housing spindle (13) and the end of which facing away from the inner body (12) is supported on a control element (20, 24) which is screwed adjustably onto the threaded end of the spindle (13) for setting the spring preloading force.
7. Bulk material grate cooler according to one of the preceding claims, characterized in that the inner body (12) is mounted rotatably at its bush (17) on the regulator housing spindle (13) and is designed as a vane wheel for bringing about rotation of the inner body driven by the cooling air flow (10) guided through the regulator housing (11).
8. Bulk material grate cooler according to one of Claims 1 to 7, characterized in that that surface of the inner body (12) acted on by the cooling air has cutouts (19) such as perforations so that a minimum cooling air flow (10) is also maintained when the inner body (12) reaches its highest position.
9. Bulk material grate cooler according to one or more of Claims 1 to 8, characterized in that the cooling air quantity regulating devices (11) arranged below the cooling grate of a bulk material cooler are arranged both on stationary and on moving zones of the cooling grate (27 to 29).

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